Cardiac arrhythmia includes different types of abnormal or irregular heart rhythms, such as, for example, atrial fibrillation (AF), which is characterized by rapid and irregular beating. Under normal heart conditions, a heartbeat is produced by electrical pulses (i.e., signals) which originate in the upper chambers (i.e., atria) of the heart and pass through the atria through the atrioventricular (AV) node to a pair of lower chambers (i.e., ventricles) of the heart. As the signals pass through the atria, the atria contract and pump blood from the atria into the ventricles. As the signals pass through the AV node to the ventricles, the ventricles are caused to contract, pumping out blood from the heart to the body. During conditions of AF, however, the signals in the atria become chaotic and cause the heart to beat irregularly.
AF can negatively affect the physical, psychological and emotional quality of a person's life. AF can progressively increase in severity and frequency and, if left untreated, may lead to chronic fatigue, congestive heart failure or stroke. One type of AF treatment includes prescribed medications, such as rhythm control medications and medications used to manage the increased risk of stroke. These medications must be taken daily and indefinitely. Another type of AF treatment includes cardioversion, which attempts to restore a normal heart rhythm by providing electric shocks to the heart through electrodes placed on the chest. In some persistent types of AF, cardioversion is either ineffective or cannot be attempted.
Recent approaches for treating AF include minimally invasive ablation procedures (e.g., catheter ablation) in which the heart tissue is ablated to terminate electrical pathways and block faulty electrical impulses that can cause heart rhythm disorders.